title: [Role of muscarinic cholinergic receptor subtypes in regulating glutamatergic synaptic transmission in rat spinal dorsal horn].
abstract: OBJECTIVE
  To investigate the role of muscarinic cholinergic receptor (mAChR) subtypes in the regulation of glutamatergic input to the spinal dorsal horn neurons and the possible mechanism.
  
  
  METHODS
  Whole-cell voltage-clamp recordings on acute spinal slice was utilized to investigate the effect of activation of mAChRs and blockade of M2/M4 subtypes on glutamatergic synaptic transmission in rat spinal dorsal horn neurons.
  
  
  RESULTS
  The nonselective mAChRs agonist oxotremorine-M concentration-dependently decreased the amplitude of monosynaptic and polysynaptic evoked glutamate-mediated excitatory postsynaptic currents (eEPSCs) in most of the neurons. The M2/M4 antagonist himbacine completely blocked the inhibitory effect of oxotremorine-M in 92.3% of monosynaptic and 75% of polysynaptic neurons in the spinal cord slices. In the remaining 16% neurons, himbacine partially blocked the inhibitory effect of oxotremorine-M.
  
  
  CONCLUSIONS
  Activation of mAChRs in the spinal cord attenuates synaptic glutamate release to the dorsal horn neurons mainly through M2 and M4 receptor subtypes, indicating that a presynaptic inhibition in the spinal cord may be involved in the regulation of nociception by the cholinergic system and mAChRs.
authors.affiliation: Department of Anesthesiology, General Hospital of PLA, Beijing 100853, China. duweiybyb@163.com
authors.forename: Wei
authors.initials: W
authors.lastname: Du
authors.forename: Ying
authors.initials: Y
authors.lastname: Guo
authors.forename: Weixiu
authors.initials: W
authors.lastname: Yuan
mesh_terms: D000818:Animals; D019706:Excitatory Postsynaptic Potentials; D005260:Female; D018377:Neurotransmitter Agents / Q000378:metabolism*; D020671:Posterior Horn Cells / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011976:Receptors, Muscarinic / Q000378:metabolism*; D009435:Synaptic Transmission
chemical_list: D018377:Neurotransmitter Agents; D011976:Receptors, Muscarinic